Matrix metalloproteinases (“MMPs”) are a family of enzymes, including, collagenases, gelatinases, matrilysin, and stromelysins, that are involved in the degradation and remodeling of connective tissues. These enzymes are contained in a number of cell types that are found in or are associated with connective tissue, such as fibroblasts, monocytes, macrophages, endothelial cells and metastatic tumor cells. They also share a number of properties, including zinc and calcium dependence, secretion as zymogens, and, 40–50% amino acid sequence homology.
Matrix metalloproteinases degrade the protein components of the extracellular matrix, i.e., the protein components found in the linings of joints, interstitial connective tissue, basement membranes, cartilage and the like. These proteins include collagen, proteoglycan, fibronectin and lamanin.
In a number of pathological disease conditions, however, deregulation of matrix metalloproteinase activity leads to the uncontrolled breakdown of extracellular matrix. These disease conditions include arthritis (e.g., rheumatoid arthritis and osteoarthritis), periodontal disease, aberrant angiogenesis, tumor metastasis and invasion, tissue ulceration (e.g., corneal ulceration, gastric ulceration or epidermal ulceration), bone disease, HIV-infection and complications from diabetes.
Administration of matrix metalloproteinase inhibitors has been found to reduce the rate of connective tissue degradation, thereby leading to a favorable therapeutic effect. For example, in Cancer Res., 53, 2087 (1993), a synthetic matrix metalloproteinase inhibitor was shown to have in vivo efficacy in a murine model for ovarian cancer with an apparent mode of action consistent with inhibition of matrix remodeling. The design and uses of MMP inhibitors are reviewed, for example, in J. Enzyme Inhibition, 2, 1–22 (1987); Progress in Medicinal Chemistry, 29, 271–334 (1992); Current Medicinal Chemistry, 2, 743–762 (1995); Exp. Opin. Ther. Patents, 5, 12871296 (1995); and Drug Discovery Today, 1, 16–26 (1996).
Matrix metalloproteinase inhibitors are also the subject of numerous patents and patent applications, including: U.S. Pat. Nos. 5,189,178; 5,183,900; 5,506,242; 5,552,419; and 5,455,258; European Patent Application Nos. EP 0 438 223 and EP 0 276 436; International Publication Nos. WO 92/21360; WO 92/06966; WO 92/09563; WO 96/00214; WO 95/35276; and WO 96/27583.
Further, U.S. Pat. Nos. 6,153,757 and 5,753,653 relate to prinomistat and its synthesis, the disclosures of each are incorporated herein by reference in their entireties.
Prinomastat, shown below, is a potent inhibitor of certain metalloproteinases (MMP), particularly matrix metalloproteinases and tumor necrosis factor-α convertase. International Publication No. WO 97/208824 discloses the chemical structure of prinomastat, its pharmaceutical composition, as well as pharmaceutical uses, methods of its preparation and intermediates useful in its synthesis.

Until now, metabolites of prinomastat have not been identified, isolated, purified or synthesized. Further, it is shown that some of these metabolites are potent matrix metalloproteinase inhibitors.